AWARENESS DURING SURGERY - NEW APPROACH

With modern light anesthesia the problem of awareness during surgery has defied analysis, because no physical sign reliably signals the conscious level. A test was developed which entails direct communication with the patient at the end of surgery, noting the earliest moment after withdrawal of nitrous oxide at which he makes the appropriate response to a verbal request, the time to correct response (TCR). This test showed premedication with lorazepam 4 mg/70 kg to be significantly better than morphine 10 mg of ensuring unconsciousness when the main anesthetic agent was nitrous oxide, in 2 groups of patients undergoing abdominal surgery. All patients who had lorazepam were able, on request, to hold up the head a few minutes after surgery. Thus the benefits of light anesthesia were retained while ensuring unconsciousness.